And so in the 21st week they finally nailed it with two words they never intended to write. 8.53pm on an intense, cold, dark and sometimes violent Sunday night and something terrible had happened. The question was: what? Like some odd twist on Orwellian doublethink, like some odd twist on their doublethink, not knowing was knowing everything. Marca's website was down. Those typing www.marca.com were greeted instead by a simple message:

Forbidden Error.

You couldn't make it up, which is ironic really. But there it was in a nutshell: forbidden error. This was a forbidden error, all right – the most forbidden of all. A technical problem had delivered the perfect verdict and the perfect punchline. And, like all great comedy, the secret was in the timing. At 20.53, the unthinkable had happened; the world turned upside down. Jellyheaded referee César Muñiz Fernández had looked at his watch. It said: 95.35. It was time. At 20.53, the final whistle went at the Reyno de Navarra stadium in Pamplona.

You could be forgiven for thinking that the system had gone into meltdown, wires fizzing and sparking, a digitalised voice like a Dalek bleating "malfunction, malfunction" before slumping to a halt with a fading electronic "boooop"; you imagined them running round the control centre, sweat pouring across faces illuminated red by flashing warning lights, screaming: "Shut it down! Shut it down!" while someone sinister simmered in the shadows. Ignore it and it'll go away; silence it and it never happened. Or maybe it was more basic, more childish than that. The technical equivalent of sticking your fingers in your ears and going: "La, la, la, la, la! I AM NOT LISTENING, la, la, la!"

But they were listening and they were watching. There was no getting round this one. Madrid had lost 1-0 to Osasuna. For all the mitigating circumstances – the extra balls thrown on to the pitch by fans when they tried to attack, Cristiano Ronaldo complaining that all their opponents had done was "kick us" – they had deserved to lose too. They couldn't even complain about the referee this time. Not that that stopped José Mourinho. When Barcelona came here, he recalled (probably rightly), they should have had a penalty given against them.

Madrid had two shots on target in 90 minutes and just one clear chance. Ronaldo, largely kept at a distance, was reminiscent of a trembling small-time gangster bursting out the kitchen to open fire on Jukes Winnifield. Lassana Diarra and Sami Khedira had the flair and creativity of a lump of wood. And the night's outstanding player, producing an immense display, was Carlos Aranda, a Madrid youth-teamer whose record reads "Champions Leagues played, two; Champions Leagues won, two" and who now plays for Osasuna.

Worse, the result appeared to confirm a worrying trend which poses a number of questions. Just not many about whether Mourinho is the right man: despite his complaints of being under attack, he has had a level of protection that Manuel Pellegrini could only dream off.

Madrid have now dropped 12 points away from home – two at Mallorca, Levante and Almería and three at Osasuna and Barcelona. The last four clubs they have failed to beat were 17th, 18th, 20th and 2nd when they played them; Mallorca, whom they faced on the opening day, are currently 11th. Three of the bottom five have taken points from them. They have not scored more than one in any of their past five. Implausibly brilliant though he has been, can a team always rely on Ronaldo? Do they have the creativity against teams that close up? How badly do they miss Gonzalo Higuaín? Can they survive without Xabi Alonso, in whose absence they desperately lack fluidity? Why hasn't Mourinho rotated? Can Mourinho rotate? Are they tired? Is the squad good enough? ("No", says Marca's editor this morning – the same Marca editor who previously declared it "the best squad in the world".) Did that battle over a striker – a battle Mourinho eventually won – do them damage?

Problems, problems. But, let's face it, they're not really the problem. And it was not just about this defeat, it was about what it meant. It was about the context as much as the content. It is not that the final whistle blew on the match at 20.53 last night, it was that the final whistle blew on the league title. In 2007-08, Madrid won the league in Pamplona; last night, they lost it there. Pamplona, one headline had it, was their "Waterloo". And we're not even in February. Last night could have been excused as a simple error but it was a forbidden one. And when www.marca.com was finally up and running, the headline said: "The league escapes Madrid". Over at El Mundo Deportivo, they were talking about a "death blow" and in the primate enclosure that doubles up as the studio for late-night mass debate show Punto Pelota, even mad Madridista Tomás Roncero announced: "Fighting for the league only to lose it in week 36 is a waste of effort now."

In the crush in the corridor at the Reyno de Navarra, Madrid's players were insisting that it's not all over. Which of course they had to. But, said the man on the radio, "no one believes them – not even them" – 85% of those polled by Marca said the league title was finished. All the fish was sold.

This morning's papers continued in the same vain. In Marca, Roberto Palomar was imagining the Spanish league as a supermarket, with the PA announcement echoing: "FC Barcelona to our offices, please; Barcelona to our offices. You have a league trophy to collect." Santi Segurola had them "on the edge of the abyss". Madrid had been "KO'd". Sport said Madrid were "sinking". "Colorín, Colorado …" declared SportYou – two words that are always followed by: "The End". "The league is dead! Long live the Cup! Long live the Champions League!" cried AS's cover. Inside, Roncero was still rambling. This, he said, "is a total write-off: a team that can't win at Mallorca, Levante, Almería and Osasuna cannot expect to win the league."

But it is not just about those games. It is also about other games. Barcelona's games. As one Madrid first-teamer put it privately way back in the summer: "We're not the problem; Barcelona are." If 85% of supporters throwing in the towel sounds too much with 17 games still to go, consider this: Madrid now trail Barcelona by seven points – Villarreal are closer to them than they are to Barça – and that's a gap they've not turned around before. It's also effectively eight points, because if the teams finish level, head to head goal difference decides. And Barcelona won the first game 5-0. Last night, some even floated the idea that Barcelona might almost gift them the second clásico in April – by resting their players for the Copa del Rey final three days later, safe in the knowledge that the title race is sewn up.

It isn't, of course. But you can understand why most people thought it was; you could understand the meltdown, the search for solutions. The panic. Manuel Pellegrini never slipped more than five points behind and he was sacked. That said, his team had picked up fewer points than Mourinho's have at this stage. And that's the point. The gap is effectively eight points in 17 games, which would be nothing but Barcelona have only dropped five in 21. Those five came early on, too: they have now won 15 on the trot – a new La Liga record. Madrid would lead any league in Europe except this one. Alvaro Arbeloa put it best: "Anywhere else, with a seven-point gap we'd still be in the race, but in this league it's very, very hard."

Losing in Pamplona is not particularly abnormal – Madrid have lost 11 of 33 there. What is abnormal is the number of points being racked up. What is abnormal is the pressure and the obligation that lays on a team. In a league in which draws are the new defeats, defeats are the end. A forbidden error.

"Time to go out for copas," ran the Marca's punning headline. Time to go for the Copa del Rey and the Champions League, time to go for a drink. For the second time, they were right. Time for a drink. After the night they'd had, they needed one.

Talking points

• Barcelona. New record. Goals. Messi. Etc. Etc.

• Atlético Madrid are out of the Cup. The rumours insisted that their players were soon to be out of the club. And the club's majority shareholder was out of his mind, Miguel-Angel Gil Marín boasting that he had turned down a huge bid for Sergio Agüero only for the club's president, Enrique Cerezo, to roll his eyes. "If I had been here, this would not have happened," he said, when he got back from Miami where he had been celebrating Enrique Cerezo day (no, really). Like nothing bloody stupid ever happens when he's around. Meanwhile, the fans were getting more and more agitated. So, amidst the fall out, Atlético decided to use yesterday's game with Athletic Bilbao to celebrate 100 years of wearing red and white stripes. Meanwhile, the coach Quique Sánchez Flores described it as an "amnesty", a "peace match", a day for "happiness".

So how did that go? Ah. Atlético lost 2-0 to an Athletic Bilbao side who may, just, be able to challenge for a Champions League place and ended with the fans chanting for the head of Gil Marín, whistling and booing Diego Forlán and, in the pouring rain, deciding that they were leaving early. Very early. It was a pretty bad performance (just for a change, like) and although Quique will stay in a job this week at least – because no one sees any point in burning a new coach with a defeat at Camp Nou on Saturday night – he may not be around for very much longer.

• Oh, the irony. Atlético fans chanting "Gurpegui, you're a junkie" … while puffing away on the funny fags. They also chanted for Gurpegui to die and continued to shout abuse about Aitor Zabaleta – the Real Sociedad fan that was killed by supporters from Atlético's ultras. Charming. And completely ignored.

• Deportivo in quite entertaining shock! Their match with Sevilla finished 3-3 on Saturday night but goodness knows how. Sevilla did absolutely nothing but somehow found themselves back at 2-2 having been 2-0 down and a man down after Andres Palop, who still had the bloody cheek to complain, made a save outside the area. He'll miss the Copa del Rey semi-final against Madrid on Wednesday. Sevilla fought back with two extremely spawny goals, then Alvaro Negredo scored a brilliant goal to make it 3-2. But Depor got what they deserved – yes, they really did deserve it – with a 88th-minute equaliser. The linesman's flag went up but play continued, the referee waving an advantage. Furious, Sevilla's players surrounded the linesman in protest and so did serial wind-up merchant and match day delegate Cristobal Soria. But however bonkers they went, there was one flaw in their argument: the ref was right.

• That's when the rain came down, pouring down. And yet Real Sociedad-Almería continued. The pitch was a joke. For Almería, the result wasn't. And nor were the rest of the weekend's results: Zaragoza, Sporting, Levante, and Osasuna all won, leaving Almería are second bottom. Still, at least Málaga lost. Again.

• Three wins in a row? 4-0 at Mallorca? 12th place? Four points clear of the relegation zone? Are we talking about the same Sporting?

• And this column has a new hero. Hércules midfielder Francisco Farinós. After seven months out injured, he finally came back as a sub this weekend … and was almost immediately sent off for two yellow cards against Barcelona. But did he whinge and whine and moan? Did he bitch about the refs being out to get him? Did he spy a conspiracy? No. He put his head in his shirt and screamed at himself. "We won't appeal the cards because they were both cards," he said afterwards. "I acted like a little kid – I didn't need to make those challenges, I was just so overexcited. It's all my own fault." Farinós, we salute you.

• Gah! Given in again. OK, OK, Barcelona have equalled a record that has stood for half a century by winning 3-0 at Hércules at the weekend. Pedro got the opener – he's now scored in the last six, the best run at the club since the Original Ronaldo in 1996-97. Over 20 goals in all competitions enhance his claim to be the league's player of the season, beyond the obvious pair. (Perhaps after Rossi for Villarreal – who scored a belter to beat Espanyol). Messi meanwhile had just about his worst game for weeks … and scored twice.